Novel urea derivatives



United States Patent many No Drawing. Filed Nov. 23, 1964, Ser. No. 413,330 Claims priority, applicatig: Germany, Nov. 27, 1963,

4 Claims. (51. 260-453) This invention relates to new urea derivatives, especially to derivatives of l-phenyl-3-isobntyne-(2)-oxyurea. The new compounds have good herbicidal activity. In

3,277,141 Patented Oct. 4, 1966 pounds is their good solubility in oils of diiferent kinds, e.g. waste oils or hydrocarbons. Some of the compounds are sirupy, the others are solid. It is also advantageous that their after-effect in the soil is short.

The said compounds may be prepared from nreas in which the first N bears a por m-chlorophenyl, a p-, mor o-methyl or a p-, mor o-ethyl radical and the second N bears a hydroxy radical in addition to a methyl radical, by reaction with but-yne-(1)-halide-(3). Theymay also be prepared from a-isobutynylhydroxylamines and substituted or unsubstituted phenylisocyan-ates or substituted phenylcarbamic acid derivatives. The various possibilities of preparation are illustrated, by the following reaction formulae:

OH; on. QN-co an @NHCON/ YCH-CEOH 011 2:. \OH on.

on, acid acceptor N H-C ON/ X. o CHOECH particular, they have excellent selective herbicidal activity for the control of unwanted vegetation growing among crop plants, without being injurious to the latter.

Where Y denotes chlorine or bromine It is known that urea derivatives of the N-phenyl-N methyl-N -met hoxyurea type are used for the control of unwanted vegetation. Their selectivity however is not suflicient.

We have now found that urea derivatives having the formula Xu 0 CHE-CECE where X denotes hydrogen, chlorine or alkyl and n denotes 1 or 2, X and X being identical or difierent, have excellent selective herbicidal activity. Agents containing such urea derivatives are preferably applied after emergence of the crop plants. The said urea derivatives have the added advantage of being easily emulsifi-able, which is desirable from the point of view of application technology. Another valuable property of the com- OCHCECH acid acceptor (or, if desired, catalyst) OCH-CECE where Z denotes halogen, alkoxy or phenoxy. X and n have the meanings given above.

Examples of good, active substances are: N-phenyl-N-methylN'-isobutyne-(2)-oxyureasirupy Analysis.Found: 12.8% N. Calc.: 12.83% N. N-3,4-dichlorophenyl-N-methyl-N'-isobutyne (2) oxyurea: melting point, 106 to 107 C.

Analysis.-Found 24.7% Cl. Calc.: 24.75% Cl.

Example 1 In a greenhouse, Indian corn (Zea mays), carrots (Daucus carota), onions (Allium cepa), kidney beans (Phaseolus vulgaris), peas (Pisum sativum), cotton (Gossypium spp.), millet (Panicum satz'vum), white mustard (Sinapis alba), chamomile (Matricaria chamomilla) and a mixture of weeds consisting of sour dock (Rumex acetosa), chickweed (Stellaria media), tufted vetch (Vicia cracca), amaranth (Amaramhus retroflexus) and ribwort plantain (Plantago lanceolata), having an average height of 7 to 22 cm., were sprayed with N-p-chlorophenyl N methyl N'-butyne-(1)-oxy-(3)-urea (I) in amounts of 0.75 and L kg. per hectare of active substance and, for purposes of comparison, with the same amounts of N-3,4-dichlorophenyl-N-methyl-N'-methoxyurea (II) and N-p-chlorophenyl-N'-methyl-N-met-hoxyurea (IH), each dispersed, with the addition of sodium lignin sulfonate, in 600 l. of water per hectare. Two weeks after treatment it was found that N-p-chlorophenyl-N-methyl-N-butyne-( 1)-oxy-(3 )-urea had much greater plant compatibility than H and III, particularly with carrots and Indian corn, while having the same effect on the weeds.

In the following table the degree of the damage caused to the plants is indicated in percent:

4 in amounts corresponding to 1.5 kg. per hectare, each dispersed, with the additionof sodium lignin sulfon-ate, in 500 l. of water per hectare.

Four weeks after treatment the herbicidal effect of the substances was determined. The degree of the damage caused to the plants is indicated in the following table (in terms of percentage):

Active substance I II III Rate of application, kg.ll1a 0.75 1.5 0.75 1.5 0.75 1.5

Crop plants:

Indian corn 0 0-10 60-70 70-80 35-50 50-60 0 3 50 50 75 25 100 100 70 90 25 100 100 40-60 70-80 80 80 50-60 60-80 Cotton 15-20 15-20 100 100 100 100 Unwanted plants:

Millet 100 100 90-100 100 90 90-100 White mustard 100 100 80-90 80-100 90 80-100 Chamomile 90-100 90-100 80 90-90 80 90 Mixture of weeds 95 95 95 95 95 95 N 3,4 dichlorophenyl=N'-methy1-N'-butyne-(1)-oxy- (3)-urea has an activity similar to that of N-p-chlorophenyl N methyl-N'-butyne-(l)-oxy-(3)-urea. N-3- chloro 4 methyl-phenyl-N-methyl-N'-butyne-(l)-oXy- (3)-urea also has good selective herbicidal activity.

Example 2 Plastic pots were filled with clayey sandy soil and sown with Indian corn (Zea mays), barley (Hordeum vulgare), wheat (T riticum sativum), rye (Sec'ale cereale), carrots (Daucus carota), onions (Allium cepa), peas (Pisum sativum), cotton (Gossypium spp.), charlock (Sinapis arvensis), chamomile (Matricaria chamomilla) and small nettle (Urtica urens). The soil was then sprayed with N-p-chlorophenyl-N-methyl-N'-methoxyurea (V) and N-3,4-dichloropheny1-N-methyl-N'-methoxyurea (IV),

The following substances have similar activity:

N-m-methylphenyl-N'-methyl-N-isobutyne-(2)-oxyurea,

N-p-methylphenyl-N'-methyl-N'-isobutyne-(2)-oxyurea,

N-3-methyl-4-chlorophenyl-N'-methyl-N-isobutyne-(2)- oxyurea,

N-3-chloro-4-methylphenyl-N-methyl-N'-is0butyne-(2)- oxyurea.

In the above compounds the term -isobutyne-(2)-oxyurea is considered the same as the term -secbut-3-ynyli oxyurea.

We claim:

1. A compound of the formula where n denotes one of the integers 1 and 2 and X is a References Cited by the Examiner UNITED STATES PATENTS 2,744,819 5/1956 Toorman 71--2.6 2,863,754 12/1958 Wain 71-2.6 2,960,534 11/1960 Scherer et a1. 260-553 2,999,110 9/1961 Lott et a1. 260553 ALEX MAZEL, Primary Examiner.

JAMES O. THOMAS, 111., HENRY R. JILES,

Examiners.

JAMES H. TURNIPSEED, Assistant Examiner.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No, 3,277,141 October 4, 1966 Gustav Steinbrunn et a1.

It is hereby certified that error appears in the above numbered patent requiring correction and that the said Letters Patent should read as corrected below.

Column 3, line 62, for "(IV)" read (VI) Signed and sealed this 29th day (if August 19670 (SEAL) Attest:

ERNEST W. SWIDER EDWARD J. BRENNER Attesting Officer Commissioner of Patents 

1. A COMPOUND OF THE FORMULA 